1. Field of the Invention
The present invention relates to a folding device for a scooter.
2. Description of the Related Art
A conventional scooter in accordance with the prior art shown in FIGS. 1 and 2 comprises an elongated base plate 1, a head tube 12, a handlebar stem 13, two side plates 10 each secured on the front end of the base plate 1, and a support rod 14 having an upper end secured on the head tube 12 and a lower end pivotally mounted between the two side plates 10. Each of the two side plates 10 defines a sector-shaped guide track 11 having a first end defining a first recess 111 and a second end defining a second recess 112. A positioning axle 141 is mounted on the support rod 14 and is detachably received in the first recess 111 or the second recess 112. A drive lever 142 is pivotally mounted on the support rod 14 for moving the positioning axle 141 between a first position where the positioning axle 141 is secured in the first recess 111 so that the support rod 14 is disposed in an upstanding manner, thereby fully expanding the scooter, and a second position where the positioning axle 141 is secured in the second recess 112 so that the support rod 14 is disposed in a horizontal manner, thereby folding the scooter.
However, the dimension of each of the first recess 111 and the second recess 112 is larger than the outer diameter of the positioning axle 141 so that the positioning axle 141 cannot be rigidly secured in the first recess 111 and the second recess 112. In such a manner, the positioning axle 141 is easily detached from the first recess 111 due to a shock or vibration to unfold the scooter, thereby injuring the safety of the user.
In accordance with one aspect of the present invention, there is provided a folding device for a scooter comprising: an elongated base plate, a head tube, a handlebar stem, a support rod mounted between the head tube and the base plate, and a support base mounted between the support rod and the base plate, wherein,
the support base includes a first side plate and a second side plate spaced from the first side plate, an arcuate slide track defined in the first side plate and having a first end defining a first insert hole and a second end defining a second insert hole, a first through hole defined in the first side plate, a first locking hole defined in the second side plate and aligning with the first insert hole, a second locking hole defined in the second side plate and aligning with the second insert hole, and a second through hole defined in the second side plate and aligning with the first through hole;
the support rod includes a bottom end provided with a transverse tube located between the first side plate and the second side plate and defining a receiving chamber located above the transverse tube for receiving therein a support tube which is rested between the first side plate and the second side plate;
a positioning axle extending through the first through hole of the first side plate, the transverse tube of the support rod, and the second through hole of the second side plate so that the support rod is pivotally mounted on the support base;
a pull rod slidably mounted in the support tube and having a first end provided with an outer thread extending outward from the slide track of the first side plate to be engaged with a pull knob which protrudes outward from the slide track of the first side plate and a second end provided with an enlarged head extending outward from the support tube and detachably received in the first locking hole or the second locking hole, and a spring mounted on the pull rod and biased between the pull knob and the enlarged head;
a guard plate mounted between the first side plate and the second side plate for supporting the support rod, the guard plate having a first side provided with a first axle and a second side provided with a second axle defining a screw hole;
a retaining piece defining an arcuate recess for retaining the support rod and having a first end pivotally mounted on the first axle and a second end defining a cut; and
a threaded insert rod extending through a guard pad and the cut of the retaining piece, and screwed into the screw hole of the second axle, and a positioning handle pivotally mounted on the insert rod.
Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings.